How to generate an unique 18 digit post ID like Pinterest?

Question

I want to create a post with random unique post ID instead of auto incremental post ID I found that for every new post in Pinterest, it has an unique 18-digit post ID such as

http://www.pinterest.com/pin/521432463078873423/

What is this 18-digit number? How to generate this number in php when creating new post?

Thanks!

Answer 1

The third option in this link allow you to specify a length when creating a GUID. BTW, Google is full of results for "Php how to create GUID".

http://phpgoogle.blogspot.com/2007/08/four-ways-to-generate-unique-id-by-php.html

<?php

//set the random id length 
$random_id_length = 18; 

//generate a random id encrypt it and store it in $rnd_id 
$rnd_id = crypt(uniqid(rand(),1)); 

//to remove any slashes that might have come 
$rnd_id = strip_tags(stripslashes($rnd_id)); 

//Removing any . or / and reversing the string 
$rnd_id = str_replace(".","",$rnd_id); 
$rnd_id = strrev(str_replace("/","",$rnd_id)); 

//finally I take the first 18 characters from the $rnd_id 
$rnd_id = substr($rnd_id,0,$random_id_length); 

echo "Random Id: $rnd_id" ;
echo "<br>";

?>